Medicine is transforming rapidly. During this era of human history, scientists are forever changing lives, because for the first time humans are not powerless against their genes! We now have the power to not only predict, but also alter our very future. The Genetic Revolution is here!
With the power of gene therapy, scientists now have a new tool that enables them to change a patient's DNA. Medical treatments usually counteract the symptoms of a disease. But with gene therapy, doctors can cure diseases. Click to learn more
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Medicine is transforming rapidly. During this era of human history, scientists are forever changing lives, because for the first time humans are not powerless against their genes! We now have the power to not only predict, but also alter our very future. The Genetic Revolution is here!
Potential of Gene Therapy:
Problems and Potentials
One of the most important question that must be answered is....
whether or not gene therapy is safe, reliable, and usable. To come to a decision, one must analyzes the risks and possible outcomes that gene therapy can provide.
This page is filled with information that will help you, the reader, make up your own mind.
Video on the Problems of Gene Therapy
Numbers: For gene therapy to work, it must be used on a huge number of cells, and be in cells long enough for the proper proteins to be expressed.
Location and Accuracy: Vectors must be able to correctly insert the gene into the right location and in the right cell. The inserted gene must be properly expressed.
Immune Response: The vector used in gene therapy must be able to safely deliver their genes without alerting the immune system. If the immune system is alerted, then the vector could potentially be destroyed, making the treatment ineffective. Furthermore, if the immune system is alerted it could create a dangerous systematic immune response and inflammation.
Multigene Disorders: Some common disorders are caused by multiple genes (Diabetes, Alzheimer's). These would be very difficult to treat because of their complexity, requiring a lot of very specific treatments.
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Gene therapy is a very risky procedure that could cause more harm than good, depending on the outcome.
Because this therapy deals with the very essence of life, disrupting it could be catastrophic. Inaccurate delivery of genes into the wrong place could potentially cancel out other important genes. Inaccurate delivery could also create tumors in the body, further complicating the treatment.
Gene therapy also poses the risk of inserting the gene into a patient's germline. If the gene is in the right place, and is beneficial to patients and their offspring, then it is great. If the gene is in the wrong place, it could cause disaster to patients descendants.
Gene therapy, if perfected would be considered the "panacea" of everything. All diseases, whether caused by genetic mutations or environmental problems, have a genetic origin. Thus gene therapy can cure practically everything.
It is understandable to have skepticism about such a therapeutic technique
The following is a list of disorders and diseases that scientists are trying to cure and treat through gene therapy.
Gene therapy is currently being studied for the treatment of cancer. Gene therapy offers a wide range of solution to cancer, but the lack of efficient technology is holding back current cancer treatment. One of the solution is to replace the missing or altered genes with healthy, working genes. This is great because some genes, like p53, can cause cancer if they are missing or mutated.
Scientists are also studying ways to increase a patient's immune response to cancer. In one method, a small blood sample is taken from a patient. The cell in the sample will be injected with a gene that will cause them to produce T-cell receptors (TCRs), a type of protein. The genes are transferred into the white blood cells of a patient, and are then given back to the patient. In the body, the white blood cells will produce TCRs. The TCRs will attach to the outer surface of the white blood cell and recognize certain molecules on the surface of the tumor cells. The TCRs will attach to the tumor cells and activate the white blood cells to attack and destroy the tumor cells.
In addition, scientists are also investigating the insertion of genes into cancer cells. The genes will make the cells more sensitive to various cancer treatment such as chemotherapy and radiation therapy. In order to help noncancerous cells scientists are studying ways to remove healthy blood-forming stem cells from the body and insert them with genes. The genes will make the cells more resistant to the side effects of high doses of anticancer drugs. Afterwards, the stem cells will be injected back into the patient.
Scientists are also studying ways to introduce "suicide genes" into cancer cells. A drug will be given which will activate the "suicides genes" in the harmful cells, killing them. In another approach, genes that prevent cancer cells from developing and creating new blood vessels are instead inserted.
Video on using gene therapy for cancer
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(114) The pictures on top are diagrams showing the blood vessels of cancerous cells
Video on Gene Therapy Study for Alzheimer's
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An experimental medical procedure made in 2005 at the University of California, San Diego, was one of the first medical treatment to help decelerate the rapid decline caused by Alzheimer's Disease. Although the treatment required brain surgery, it was able to slow down cognitive decline by 36 to 51 percent, a lot better then usual medication. The procedure involves removing skin cells from a patient, and using gene therapy, alter the genes to secrete the protein NGF, or Nerve Growth Factor. NGF can not be simply injected because it could cause serious side effects if moves to the wrong part of the brain. Because of this, doctors drilled holes into the skulls of patients and implant the NGF-producing skin cells directly on top of spots affected by Alzheimer's. Patients were kept under general anesthesia to keep them still after one of the patient died (five weeks later) because of bleeding in the brain caused by moving during cell implantation. New growth were found protruding out of the damaged brain cells at the implant site, showing the possibilities of gene therapy for Alzheimer's disease.
In 2001, 43 HIV-infected volunteers had experimental genes inserted into their white blood cells. 12 years later, a work published in Science Translational Medicine revealed that all patients are fine and have no side effects. Nearly every one of the volunteers still have properly working inserted genes. In 2007, Timothy Ray Brown, also known as "the Berline patient" was dying of leukemia. In addition, he was infected with HIV. Brown's doctor Gero Hütter understood that 1 percent of people of European decent have a mutation in the CCR5 receptor which makes HIV infection very difficult.To deal with Brown's leukemia, Hütter needed to find a volunteer for a bone marrow transplant. To deal with Brown's HIV, Hütter hoped to find someone with the CCR5 mutation. Hütter finally found a person, and in 2010 he published his results. The transplant eliminated Brown's leukemia, and even the most advanced test could not find a trace of HIV in Brown's body. Scientists hope to find ways to copy these results and cure AIDS.
(116) On top: "The Berlin patient"
Cystic fibrosis is a fatal genetic disease that affects about 30,000 people in the United States. In 1989 a mutation in the Cystic Fibrosis Transmembrane Regulator (CFTR) gene was found to have caused Cystic fibrosis. In 1990, scientists was able to correct the CFTR gene by adding normal copies of the gene to cell cultures grown in laboratory. Researchers were able to modify a common cold virus into a vector in 1993. The vector carried the normal genes to the CFTR cells in the lung of a patient. Current Cystic Fibrosis research have grown exponentially with the use of gene therapy.
Using an adeno-assisted virus vector, Dr. Barry Greenberg from the University of California was able to transport a gene called Mydicar, a recombinant version of the SERCA 2A enzyme found in heart muscle cells in 2010. SERCA 2A is responsible for regulating the transport of calcium between cells, and the squeezing power of a heart muscle cell. The treatment reduced hospitalizations from an average of 2.1 days to 0.2 days. Patients with the genetic dose had evidences of less rapid enlargement of the heart. The gene was a one time infusion directly into the coronary arteries with the use of a catheter-like technology. Although it has great potential, gene therapy does not reduce breathlessness fatigue, or pain caused by advanced heart failure. Nevertheless, this was a great step toward the development of gene therapy for heart failures.
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(119) Diagrams showing the different types of spinocerebellar ataxia
Scientists at Hirokazu Hirai at Gunma University in Japan were able to modfy HIV viruses to carry a gene. The gene makes the protein CRAG, which is naturally present in brain cells. CRAG can destroy the abnormal repeats which create spinocerebellar ataxia, a disorder in the same family as Huntington's disease. Although the experiment was conducted in mice, it could be expanded to humans. In addition, this treatment can be use for other disease that can cause neurodegenerative problems.
Researchers at Dana-Farber/Children's Hospital Cancer Center have been developing a treatment for sickle cell disease which involves gene therapy. Using an animal model, the researchers had announced on December 10 2012, that they have demonstrated (in an animal model) the possibility of activating a form of hemoglobin, that is unaffected by the sickle cell mutation. It involves targeting BCL11A, a molecular switch with the potential of correcting sickle cell disease. BCL11A is a transcription factor, which can cause a shift in hemoglobin production. This shift can cause our bodies to manufacture a fetal form type of hemoglobin, which is not as affected by sickle cell mutations. Fetal hemoglobin prevents the intracellular abnormalities, thus reducing symptoms and complications caused by the sickle cell disease. Scientists now hope to further develop this technology to make it more accessible and efficient.
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